This is analysis and visualization of IntelliJ community edition code history using this IntelliJ plugin and d3.js. There is no particular method behind this so if you have a suggestion for visualisation, please feel free to create an issue.
Change size chart
Shows amount of commits by day/week. Red line is one month moving average.Note downward trends around New Year and spikes in November/December which somewhat correlate with major releases.
Amount of committers
Shows how many different people committed over month/week/day. The idea is to see amount of people contributing to the project.Files changed in the same commit (2012-2013)
Shows files which were changed in the same commit at least 8 times. Thickness of edges is proportional to the number of commits. The idea is to discover de facto dependencies between files.You can click on nodes to see file names in cluster.
Committers changing same files (2012-2013)
Shows people and files they changed within a week. If file was edited by two people within a week, a link is added. If it happened at least 7 times, link is added to the graph. The is idea is to discover communication patterns and shared code ownership.Amount of commits treemap (2012-2013)
Shows a break-down of commits by package. Renamed and moved package are tracked but only current package name is displayed. The idea is to see which parts of the project have more attention.E.g. ratio between commits to production code and tests.
Commit time punchcard
Shows amount of commits at certain time of day (similar to GitHub punchcard).Sometimes there is a "lunch-time line" around 12:30 pm, not in this case :)
Time between commits histogram
(Time is tracked separately for each committer.)This distribution will probably be the same for any project, i.e. you are most likely to commit again within 5 hours or at least within a day.
Commit messages wordcloud
Some prepositions and articles are excluded as well as "idea", "ideadev" which are used for issue tracking. The idea is to see what happenes with code by observing human language.(Alt-click on words to exclude them.)